Cross-coupling of 2-methylquinolines and in-situ activated isoquinolines: Construction of 1,2-disubstituted isoquinolinones

Syntheses of 3H-1,2,4-triazol-3-ones by copper-promoted oxidative N–N bond formation of amidines with isocyanates

“…8 Cai's group reported a base-promoted Boulton Katritzky-type rearrangement of 1-(isoxazol-3-yl)ureas to form 5-(2-oxoalkyl)-2,4-dihydro-3 H -1,2,4-triazol-3-ones (Scheme 1b). 9 Based on our interest in N–N coupling and polyazacycle synthesis, 10 a [3 + 2] cyclization reaction of isocyanates with amidine hydrochlorides to form 1,2,4 triazolones is reported here. The process undergoes a nucleophilic attack and N–N bond formation with good substrate suitability and functional group tolerance.…”

Photocatalytic Proton-Coupled Electron Transfer Enabled Radical Cyclization for Isoquinoline-1,3-diones Synthesis

“…Isoquinoline-1,3­(2 H ,4 H )-dione and its analogues represent a unique class of heterocyclic structures, prevalent in natural products, drug molecules, and organic functional materials . The synthesis of these structural compounds has garnered significant interest from synthetic chemists, leading to the development of numerous strategies for the synthesis of isoquinoline-1,3­(2 H ,4 H )-diones with a practical value . Recent advancements in radical chemistry have introduced innovative synthetic approaches for constructing these frameworks via a cascade radical addition/cyclization of acrylamide derivatives, resulting in a range of valuable transformations .…”

Accessing 3,4-Dihydroquinolinone from N-Arylacrylamides via Tetralone-Mediated Energy Transfer and 1,3-Hydrogen Shift

“…The most straightforward preparatory methods are via the functionalization of the pre-existing 2-hydroxyquinoline scaffolds . In addition, Friedel–Crafts cyclization, radical cyclization, and multicomponent multicatalyst reactions can be used for the synthesis of 3,4-dihydroquinolinones. Despite their efficiencies, they usually require harsh reaction conditions involving strong acids, toxic radical initiators, and elevated temperature.…”